Bomblift trailer suspension system

ABSTRACT

A four-wheel bomblift trailer chassis having pivotally attached suspension arms arranged in a parallel linkage to support a vertically disposed kingpin and attached spindle. The rear suspension arms are arranged to pivot 90* around a point near each rear corner of the chassis and the wheels are pivotal around each respective kingpin. A hydraulic strut serves to stabilize the parallel linkage so that the chassis is supported. The chassis can be lowered to the ground by metering fluid from the internal cylinder which extends the hydraulic strut and can be raised by pumping fluid back into the cylinder.

United States Patent Klopp 5] Feb. 15,1972

[54] BOMBLIFT TRAILER SUSPENSION SYSTEM [72] Inventor: John H. Klopp,Baltimore, Md.

[73] Assignee: The United States of America as represented by theSecretary of the Air Force [22] Filed: Nov. 26, 1969 [21] Appl. No.:880,001

[52] US. Cl. ..280/34 A, 280/4323 [51] Int.Cl ..B62d 21/18 [58] Field ofSearch ..280/43.23, 124.1, 43.22, 34 R, 280/34 A; 180/22 D [56]References Cited UNITED STATES PATENTS 2,728,583 12/1955 Tucker..280/43.22 2,936,034 5/1960 Van DerLely ..280/34 3,024,040 3/1962Muller ..280/124.1 3,024,041 3/1962 Maruhn ....280/l24.l 3,139,2886/1964 Peterson ..280/34.l 3,216,739 11/1965 Drenter ..280/34 PrimaryExaminer-Leo Fn'aglia Assistant Examiner-Robert R. Song AtturneyHarry A.Herbert, Jr. and Arsen Tashjian [5 7] ABSTRACT A four-wheel bomblifttrailer chassis having pivotally attached suspension arms arranged in aparallel linkage to support a vertically disposed kingpin and attachedspindle. The rear suspension arms are arranged to pivot 90 around apoint near each rear comer of the chassis and the wheels are pivotalaround each respective kingpin. A hydraulic strut serves to stabilizethe parallel linkage so that the chassis is supported. The chassis canbe lowered to the ground by metering fluid from the internal cylinderwhich extends the hydraulic strut and can be raised by pumping fluidback into the cylinder.

2 Claims, 2 Drawing Figures BOMBLIFI TRAILER SUSPENSION SYSTEMBACKGROUND OF THE INVENTION This invention relates to an improvedsuspension system for an unusually versatile weapons-handling trailerand, more particularly, the invention is concerned with providing abomblift trailer suspension system which includes a hydraulic strut thatpermits the trailer chassis to be quickly and easily raised and loweredand pivotal linkage means which permits rotation of the wheels forsidewise movement and folding of the rear suspension assemblies forreducing the effective trailer width.

Strict limitations are placed on weapons-handling trailer design becauseof the unique features of various military aircraft with which thetrailer must be compatible. Many potential problem areas necessitate athorough investigation into the various requirements for providing theideal weapons trailer.

Some of these design problems are concerned with loading particularaircraft and include one aircraft where the inboard pylon is close tothe landing wheel and the wheel-well cover in its open position mayprevent vertical loading of the store into the pylon.

Other problems are concerned with aircraft having a bomb bay width of20-inch maximum which limits the width of the lift mechanism and, sincethe bomb bay extends downward, the vertical height of the loader is alsolimited. Another type of aircraft has pylons so close to the ground thata 20-inch diameter store on the pylon leaves only inches groundclearance. This is one of the worst cases for minimum ground clearance.

Another serious problem is the condition on an aircraft where thehorizontal clearances between the rear of the outboard fuel tanks andthe tip of the horizontal stabilizer and between the front of theinboard fuel tank and the nose fear are both unusually small. In thissituation the bomblift trailer must be capable of getting under thefuselage to load a center store. Since the fuel tanks of militaryaircraft are always loaded first, it would be most desirable andnecessary to have a trailer which can be lowered to ground level and onewhich can easily be moved laterally as well as being capable of beingreduced in width so as to fit into tight areas.

SUMMARY OF THE INVENTION The present invention provides a bomblifttrailer suspension system wherein pivotally attached parallel suspensionarms or links extend outwardly from each corner of the chassis. Avertically disposed kingpin with attached spindle is positioned betweenthe outer ends of each pair of suspension links. These kingpinseffectively permit rotation of the wheel and spindle around an axisperpendicular to the suspension links such that, when all four wheelsare rotated 90, the trailer is capable of sidewise or lateral movement.

Each of the rear suspension links of the trailer is further capable offolding by rearward rotation of the suspension arms around a pivot pointon the corners of the chassis. In this latter mode and when the rearwheels have previously been rotated 90, the resulting configurationproduces a situation wherein the working part of the trailer is reducedto the width of the chassis along allowing operation in close quartersin the normal manner.

Another adjustment which adds to the adaptability of the trailer for usewith the wide variety of aircraft and many different external stores, isthe ability of trailer chassis to be lowered to the ground. This isaccomplished by providing a hydraulic strut between the suspension arms.The strut serves to stabilize the linkage and support the chassis. Thechassis can be raised and lowered by pumping fluid into and meteringfluid out of the hydraulic strut. The lowering of the frame of thevehicle to ground level allows weapons to be placed on aircraft with lowground clearance.

Accordingly, it is an object of the invention to provide a trailersuspension system with the versatility and adaptability necessary toservice a wide variety of aircraft with many different external stores.

Another object of the invention is to provide a bomblift trailersuspension system wherein the frame of the trailer can be quickly andeasily lowered to ground level to allow weapons to be placed on aircraftwith low ground clearance.

Still another object of the invention is to provide a trailer suspensionsystem wherein all four wheels ofthe trailer can be manually rotated topermit the loaded trailer to be moved sideways in order to maneuveraround landing gear and stores already secured to external pylons.

A further object of the invention is to provide a bomblift trailersuspension system wherein the effective width of the rear section of thetrailer can be reduced to the width of the frame by folding and lockingthe rear suspension assemblies of the trailer aft oftheir normal trailposition.

A still further object of the invention is to providea bomblift trailersuspension system wherein a nydraulic strut is posi tioned between thesuspension arms for stabilizing the suspension linkage and for raisingand lowering the chassis. Shock absorber means are also attached to thehydraulic strut.

These and other objects, features and advantages will become moreapparent after considering the description that follows taken inconjunction with the attached drawings wherein like numbers are usedthroughout to identify like elements.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view of the bomblift trailersuspension system according to the invention with indications of thepivot capabilities of the elements; and

FIG. 2 is a side elevation view of the suspension system of FIG. 1showing the combination hydraulic strut-shock absorber positionedbetween the suspension arms.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to the figures,there is shown a typical suspension system 13 for a bomblift traileraccording to the invention. All four wheels 15 are independentlysuspended from the corners of the chassis 17. Except for pivoting andsteering capabilities, the front and rear suspension systems arebasically alike. In the drawings, the left rear suspension is shown. theright rear system being identical.

The suspension system includes a parallel linkage arrangement includingan upper suspension arm 19 having its inner end pivotally attached tothe upper surface of the corner of the chassis 17 where the longitudinalframe beam 21 and the lateral beam frame 23 are joined. Also pivotallyattached to the chassis 17 but on the bottom surface directly below andparallel to the arm 19 is the lower suspension arm 25.

A spindle 27 is positioned in the area between the outer ends of theupper and lower suspension arms 19 and 25, respectively, by means ofakingpin 29 which allows the spindle 27 to pivot around an axisperpendicular to the ground. The outer ends of the upper and lowersuspension arms are pivotally attached to the kingpin bracket 31 therebyproviding the required capability of parallel movement of the arms. Whenthe trailer is adjusted for movement in the normal forward or backwarddirection the chassis spring pins 33 are positioned in the manner shownin the drawings and the spindle spring pin 35 (which is found only onthe suspension system on the rear wheels) is in the center position asshown.

A suspension cylinder 37, which is a hydraulic cylinder surrounded byresilient shock absorbing means, is positioned between the pivot pointsof the outer end of the upper suspension arm 19 and the inner end of thelower suspension arm 25. The action of the suspension cylinder 37permits the trailer chassis 17 to be lowered and raised by changing theoverall length of the cylinder 37. This is accomplished by actuating thecylinder 37 which becomes shorter in the frame-lift cycle and, whenfully extended, the frame is lowered to the down position. Hence, theoverall height of the trailer may be effectively reduced for passageunder low-hanging pylons and bomb bay doors,

In addition, the hereinbefore described suspension system permits allfour wheels to be rotated 90 about their kingpins 29 thereby allowingthe trailer to be moved sideways for improved maneuverability aroundlanding gear and other objects. The rear suspension arms can, inaddition, be folded aft 90 thereby reducing the effective width of therear section of the trailer to the width of the frame making the trailereven more maneuverable in close quarters.

MODE OF OPERATION In operation, in normal trailer configuration, thechassis 17 is raised to trailing level by actuating suspension cylinder37 either by manually pumping fluid into the cylinder or by attachmentto an onboard hydraulic power pack. This procedure shortens the lengthof cylinder 37 and stabilizes the parallel linkage so that the chassis17 is supported. The chassis 17 can be lowered to the ground by meteringhydraulic fluid from the cylinder 37 thereby increasing the effectivelength of the hydraulic strut 37 and permitting the inner ends of thesuspension arms 19 and 25 to rotate downward. A locking collar (notshown) may be positioned on the hydraulic strut 37 while in the raisedposition to prevent extension if the connecting hydraulic line isruptured.

For lateral or sideways operation the front and rear wheels are rotatedabout each of their respective kingpins 29 by releasing the spindlespring pins 35 and manually pivoting the wheels. The steering linkage(not shown) on the front wheels is first disconnected and after thewheels 15 are rotated, the spindle spring pin 35 is repositioned in theproper hole thereby locking the wheels in the rotated position. Thisconfiguration permits the trailer with the stores attached thereto to bewheeled sideways into position around landing gear and stores alreadysecured to external pylons.

For work in close quarters, it may be necessary to reduce the width ofthe trailer. This can be accomplished by releasing the spring pins 33 onthe rear suspension systems after the wheels 15 have been rotated 90 asnoted above. Each of the rear suspension systems is then pivoted 90rearward around the point 38 which brings the wheels 15 back into theforwardrearward trailing mode except that they are now reduced to atracking width equaling the frame width. The pins 33 are then positionedin the holes 39 to lock the rotating parts in position. In this trackingmode the effective width of the rear section of the trailer is reducedto that of the frame thereby allowing the unit to be wheeled into manyareas which would ordinarily be too narrow to receive the cradledstores.

Although the invention has been illustrated in the accompanying drawingsand described in the foregoing specification in terms of a preferredembodiment thereof, the invention is not limited to this embodiment orto the particular configuration mentioned. It will be apparent to thoseskilled in the art that my invention could have extensive use in othertransfer and transport operations where mobility and maneuverability. aswell as versatility, are primary requirements.

Also, it should be understood that various changes, alterations,modifications and substitutions. particularly with respect to theconstruction details, can be made in the arrangement of the severalelements without departing from the true spirit and scope of theappended claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

1. In a weapons-carrying trailer having four wheels and a chassis, theimprovement comprising a suspension system at each wheel of the trailer,each of said suspension systems including an upper suspension arm havingits inner end pivotally attached to the upper surface of the chassis, alower suspension arm having its inner end pivotally attached to thelower surface of the chassis, said upper and lower suspension arms beingin parallel relationship, a wheel-holding spindle pivotally attachedbetween the outer ends of said parallel suspension arms, a kingpinvertically disposed through said spindle to permit said spindle andwheel attached thereto to rotate therearound, pln means disposed on saidspindle for locking and unlocking said spindle to permit rotation of thewheel around said kingpin and allow sidewise movement of theweapons-carrying trailer, and variable length stabilizing meanspivotally attached to said suspension system for controlled raising andlowering of the trailer chassis, said stabilizing means including ahydraulic strut positioned between the inner end of said lowersuspension arm and the outer end of said upper suspension arm, thelengthening of said hydraulic strut causing the trailer chassis to belowered to the ground and thereby permit the weapons-carrying trailer tobe used for loading aircraft stores where conditions of minimum groundclearance exist.

2. The trailer suspension system defined in claim 1, wherein a pivotmeans is attached to the rear corners of the trailer chassis to permiteach of said rear suspension systems to be rotated 90 causing said rearsuspension systems to be folded backward and inward thereby effectivelyreducing the tracking width of the rear end of the trailer to that ofthe trailer chassis.

1. In a weapons-carrying trailer having four wheels and a chassis, theimprovement comprising a suspension system at each wheel of the trailer,each of said suspension systems including an upper suspension arm havingits inner end pivotally attached to the upper surface of the chassis, alower suspension arm having its inner end pivotally attached to thelower surface of the chassis, said upper and lower suspension arms beingin parallel relationship, a wheel-holding spindle pivotally attachedbetween the outer ends of said parallel suspension arms, a kingpinvertically disposed through said spindle to permit said spindle andwheel attached thereto to rotate therearound, pin means disposed on saidspindle for locking and unlocking said spindle to permit rotation of thewheel 90* around said kingpin and allow sidewise movement of theweapons-carrying trailer, and variable length stabilizing meanspivotally attached to said suspension system for controlled raising andlowering of the trailer chassis, said stabilizing means including ahydraulic strut positioned between the inner end of said lowersuspension arm and the outer end of said upper suspension arm, thelengthening of said hydraulic strut causing the trailer chassis to belowered to the ground and thereby permit the weaponscarrying trailer tobe used for loading aircraft stores where conditions of minimum groundclearance exist.
 2. The trailer suspension system defined in claim 1,wherein a pivot means is attached to the rear corners of the trailerchassis to permit each of said rear suspension systems to be rotated 90*causing said rear suspension systems to be folded backward and inwardthereby effectively reducing the tracking width of the rear end of thetrailer to that of the trailer chassis.